Prospective Evaluation of Two iStent® Trabecular Stents, One iStent Supra® Suprachoroidal Stent, and Postoperative Prostaglandin in Refractory Glaucoma: 4-year Outcomes

Adv Ther. 2018 Mar;35(3):395-407. doi: 10.1007/s12325-018-0666-4. Epub 2018 Feb 23.


Introduction: This study evaluates long-term outcomes of two trabecular micro-bypass stents, one suprachoroidal stent, and postoperative prostaglandin in eyes with refractory open angle glaucoma (OAG).

Methods: Prospective ongoing 5-year study of 80 eligible subjects (70 with 4-year follow-up) with OAG and IOP ≥ 18 mmHg after prior trabeculectomy and while taking 1-3 glaucoma medications. Subjects received two iStent® trabecular micro-bypass stents, one iStent Supra® suprachoroidal stent, and postoperative travoprost. Postoperative IOP was measured with medication and annually following medication washouts. Performance was measured by the proportion of eyes with ≥ 20% IOP reduction on one medication (the protocol-specified prostaglandin) versus preoperative medicated IOP (primary outcome); and the proportion of eyes with postoperative IOP ≤ 15 and ≤ 18 mmHg on one medication (secondary outcome). Additional clinical and safety data included medications, visual field, pachymetry, gonioscopy, adverse events, visual acuity, and slit-lamp and fundus examinations.

Results: Preoperatively, mean medicated IOP was 22.0 ± 3.1 mmHg on 1.2 ± 0.4 medications, and mean unmedicated IOP was 26.4 ± 2.4 mmHg. Postoperatively, among eyes without later cataract surgery, mean medicated IOP at all visits through 48 months was ≤ 13.7 mmHg (≥ 37% reduction), and annual unmedicated IOP was ≤ 18.4 mmHg (reductions of ≥ 30% vs. preoperative unmedicated IOP and ≥ 16% vs. preoperative medicated IOP). At all postoperative visits among eyes without additional surgery or medication, ≥ 91% of eyes had ≥ 20% IOP reduction on one medication versus preoperative medicated IOP. At month 48, 97 and 98% of eyes achieved IOP ≤ 15 and ≤ 18 mmHg, respectively, on one medication. Six eyes required additional medication, no eyes required additional glaucoma surgery, and safety measurements were favorable throughout follow-up.

Conclusion: IOP control was achieved safely with two trabecular micro-bypass stents, one suprachoroidal stent, and postoperative prostaglandin. This microinvasive, ab interno approach introduces a possible new treatment option for refractory disease.

Trial registration: NCT01456390.

Funding: Glaukos Corporation.

Keywords: Glaucoma; Microinvasive glaucoma surgery (MIGS); Ophthalmology; Prostaglandin; Refractory glaucoma; Suprachoroidal; Trabecular; iStent; iStent Supra.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Female
  • Glaucoma, Open-Angle* / diagnosis
  • Glaucoma, Open-Angle* / metabolism
  • Glaucoma, Open-Angle* / surgery
  • Humans
  • Intraocular Pressure* / drug effects
  • Intraocular Pressure* / physiology
  • Male
  • Molteno Implants
  • Postoperative Period
  • Prospective Studies
  • Prostaglandins* / analysis
  • Prostaglandins* / metabolism
  • Sclerostomy / instrumentation
  • Sclerostomy / methods
  • Stents / classification*
  • Trabecular Meshwork / drug effects
  • Trabecular Meshwork / physiopathology
  • Trabeculectomy / methods*
  • Travoprost / therapeutic use
  • Treatment Outcome
  • Visual Acuity


  • Prostaglandins
  • Travoprost

Associated data